Posted on 07/27/2006 5:46:11 PM PDT by KevinDavis
An ion engine several times more powerful than any previously flown is being tested by NASA. It could propel a spacecraft all the way to Saturn's moon Titan. Ion engines operate by removing electrons from atoms of a gas – usually xenon – and then accelerating the resulting ions through an electric field. The ions are shot out the back of the engine to create thrust.
The engines provide much less thrust at any given time than do rockets. But they are much more fuel efficient, providing a steady source of propulsion that could ideally be used to take spacecraft to the outer solar system.
NASA tried out ion engines on its Deep Space 1 mission, which launched in 1998 and visited an asteroid and a comet at a distance of 203 million kilometres from the Sun. But the so-called NSTAR engines used on that mission were not powerful enough for more distant excursions.
A new engine called NASA's Evolutionary Xenon Thruster (NEXT) can generate 2.5 times as much thrust as the NSTAR engine and would enable more ambitious missions. The engine was built by Aerojet, an aerospace company based in Sacramento, California, US.
(Excerpt) Read more at newscientistspace.com ...
Interesting physics, but we were just born too soon.
Theoretically, however, couldn't a Jovian payload pack enough ballistics for a return trip while letting the Ion plant do the distance running?
[I'm a layman. Isn't the engineering term "gravity well"? 20 kW isn't that much power, particularly that far out, it seems.]
I'd be more interested in NASA developing an engine which could propel a reasonable-sized payload from Earth orbit to Lunar orbit in 12 hours or less.
Interesting economics there: whoever builds the first habitable lodging at Hotel Luna probably gets the proprietary rights to the reasonable 12-hour commuter craft.
Ion Powerrh!
A little bit of a steady push goes a long way in space.
Don't start counting on this developing any time soon. Orbital maneuvering is never in a straight line, and it is never straight forward. To achieve your 12 hour goal, you'll need a revolutionary new engine, and passengers would probably have to endure very high accelerations on both ends of the maneuver. I'm not even sure if people could endure the necessary accelerations to meet the 12 hour goal.
So is this thing supposed to accelerate faster than ordinary ion engines, or were the normal engines too weak to accelerate enough to get to Saturn?
put 'em in fluid-filled capsules for G endurance.
I'm inclined to agree. I have actually seen an ion engine. It was at the Hughes Research Labs (HRL) in Malibu in 1962.
In those days the big technical issue was solving the problem of charge buildup as you fire the positive and negatively charged ions out the back. Seems like it shouldn't be that hard - you just fire an equal number of them charge-wise. In fact it must be a much more difficult problem because it was the focus of ion engine research for many years and, for all I know, it still is.
I'm pretty sure this is where U.S. ion engine development began probably some time earlier than when I first saw the HRL Ion Engine Lab. So here we are 44 or more years later and the progress isn't exactly following and ion engine version of Moore's Law. Nevertheless, the ion engine has it's place and someday we will have a useful system (I hope.)
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